PREP 1-5 求助

5.    304-!-item-!-187;#058&000163?? 答案为什么是E

If k is an integer and 2 < k < 8, what is the value of k ?

(1) k is a factor of 30.

(2) k is a factor of 12.

C

30= 2*3*5 , (factor: 5, 6)

12=2*2*3 ,( factor 6 , 4,),   6 相同啊

yun... 看漏了3, 看来DS要非常非常小心..

谢谢楼上的.